0 pitch longerons.
That may be true in the RV-7 but for the the 10 Van explicitly instructs to use the door sill and the seat back as leveling surfaces.
Don't remember exactly but the longeron on the 10 was about 3 degrees off.
I
Here is the email response I received from vans and my original question. I was originally planning to implement a platform on the longerons but i am now concerned that their accuracy while consistent may not be quite sufficient. I also have doubts about the clearance to the seatbelt mounts. I am therefore going to change my strategy and implement a similar platform to those depicted when I have completed fuselage attachment...
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The longerons are the 0 pitch reference for the airplane so it's OK to mount
the AHRS to them. Typically builders put this a long way back in the tailcone
so the bridge is shorter (less susceptible to vibration)
Vans
Forwarded by: Support
Forwarded to: gusf
Date forwarded: Mon, 03 Jun 2013 08:06:04 -0700
Subject: Mounting dynon adahrs in the tailcone question
From: Paul Hamilton <
[email protected]>
Date sent: Sat, 1 Jun 2013 18:03:19 +1000
To: "
[email protected]"
<
[email protected]>
I am starting to work on the platform for my dynon adahrs to be
mounted in the tailcone of the RV-10. I looked at the AHRS platform
that you sell, but it does not meet the dynon requirements due to
the proximity of electrical components. I am thinking of building a
platform between the longerons but it needs to be within 1 degree of
parallel to all three axes. Are you able to confirm that the
longerons are indeed 0 pitch? If they are not, can you recommend a
location to mount the adahrs that would conform?
Cheers
Paul L Hamilton
Vans RV10 Builder 41387